Sintering and smelting ore.



A. S. DWIGHl.

SINTERING AND SMELTING ORE.

APPLICATION FILED MAR.3I.1910. RENEWED JUNE 15. I916.

1,215,635. Patented Feb. 13,1917.

H IHHI TIZ HHHIH I ZZYZW/ ores, filed June 25, 1908, Serial No. 440,404.-

ARTHUR S. DWIGHT, OF NEW YORK, N. Y.

} sm'rnnme AND smnL'rme one.

Specification of Letters Patent.

Patented Feb. 13, 1917.

Application filed March 31, 1910, Serial No. 552,578. Renewed June 15, 1916. Serial No. 103,863.

To all whom it may concern:

Be it known that I, ARTHUR S. DWIGHT, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Sintering and Smelting Ores, of which the following is a specification, reference being had therein to the accompanying drawing.

Thisinvention relates to improvements in processes for treating ores, particularly those which are susceptible of a d e sulfurizing or kindred treatment and a sintering treatment, either simultaneously or successively, and of being subsequently reduced by smelting or a similar operation.

It will be understood that my improved process is not limited to the treatment of ores normally containing a combustible element, such as sulfur, but may be used for the treatment of iron or other ores to which a combustible element, such as carbon, has been artificially added.

The process .is similar in some respects to that set forth in my co-pending application entitled Desulfurizing' and smelting I do not, therefore, herein claimthe broader features of the process set forth in the said application.

The essential steps of the process to which my invention relates can be carried out in apparatus of any of a number of forms. In the accompanying drawings I have shown for purposes of illustration one form of apparatus adapted for use in'the practice of my invention.

Of the drawings- Figure 1 is a side view partly in elevation and partly in vertical section and shows an apparatus adapted to be used in carry-' ing out my improved process. 1 Fig. 2 is a plan view, a part being shown in cross section along the 7 line: 22 of Fig. 1.

Fig: 3 is a fragmentary cross sectional view taken alon the line 3-3 of 2.

It will pbe 'un' erstoodthat the a paratus presented "in the drawings is ustrated more'or less conventionally but in such a considered, the process can be regarded as comprising two stages, and the devices illustrated for carrying out the process can be considered as made up of two main parts.

The apparatus indicated by A is especially adapted for treatment of sulfid ores, such as copper sulfid, although it is to be understood that the invention is not limited to the treatment of material of any particular type.

The apparatus indicated by A comprises a traveling conveyer 1. This conveyer 1 may be of: any desired type, but I prefer to use a conveyer comprising a series of pans, buckets or pallets 2. These pallets are provided with perforated bottoms and side walls perpendicular to the bottoms. Wheels 3, 3 are provided for each pallet and these wheels are adapted to engage with and be supported by the tracks 4 and 5. The pallets are adapted to aline with each other at the upper part of the conveyer to form a continually moving tray or platform sup- I way that thees'sential parts ofthe process and of the apparatus may be re'adily under- Pp stood by those skilled in the art. Generally ported by the track 4. At its forward end the track 4 is overlapped by the track 5 in,

such a way that'a pallet on passing around the curved end of the track 4 will be engaged by the overlappin curved end of the track 5 on which it will e carried by gravity to the continually rotating wheel 6.

This wheel is provided with teeth adapted to engage the wheels of the pallets and to thus carry the inverted pallets upward onto the track 4. l

A hopper 7 is provided for. the. reception of material and serves to direct the material onto the moving'conveyer in a stream or layer of substantially uniform thickness.

8 represents an air boxqprovided with means for, exhausting the air therefrom. The top of this box is formed by the perforated bottoms of the moving pallets and consequently as air is withdrawn from the box by the exhausting means it, is drawn" in through the perforationsin the pallet bottoms. When there is a. layer of ore on the pallets then the air. will be drawn downward through the interstices between the" ore fragments.

\ represents an 'ignitin may be of'any preferred". orm, such as a gas ipe perforated to rovide a series of, gas;- ets across the top 0 the ore mas 's or. econ-.-

apparatus which the sintering of the ore, as these are fully described in patents issued to A. S. Dwight and R. L. Lloyd, among them being Patent 882,517 and Patent 882,518. For the purposes of the present description, it is sufiicient to say that the ore-moves along with the conveying-apparatus 1, and that the I combustion started by the igniting device 9 moves gradually downward through the stream or layer of ore under the influence of the downward draft of air caused by the exhausting device connected with the air box 8. The combustion is entirely, supported by the combustible elements, such as sulfur contained in the ore itself, and the lines of combustion move downward until they reach the bottom of the layer. The

- heat generated by the combustion causes certain constituent elements of the ore mass to melt and unite the layer into a homogeneous coherent porous cake. The rate of motion of the conveyer 1, and the thickness of the layer of ore are so regulated that the desulfurizing and sintering processes will be completed when the moving layer reaches the point 10. As each pallet reaches the point 10, it is moved out of alinement with the other pallets and is returned by gravity to the wheel 6. At the same time thecontinuous movement of the sintering cake, which is indicated in the drawings by 11 carries it onto a supporting shelf 12 which {sin alinement with the bottoms of the palets.

B represents as an-entirety the furnace for smelting the sinter cake. This furnace comprises side and end walls 13, a bottom 14. and an arched roof 15. The various parts o the furnace may be formed of any suitable heat resisting materials which are adapted for use in connection with the ore to be treated.

In one end wall of the furnace provided an aperture 16 adapted to receive the end of the continually moving sinter cake 11. I prefertoso construct the conveyer 1 that the sinter cake will be fed into the furnace at a slight downward angle, the purpose of which will be hereinafter fully set forth. If desired, supporting ledges of fire brick may be formed to support the advancing sinter cake. I do not, however, at present consider these ledges necmry and have not therefore shown them inthe draw a I The bottom (if-the furnace is adaptedifor the collection and retention of a bath of matte or molten metal. A tap 17 is proand below the moving sinter cake.

there is vided for the withdrawal of the metal from time to time. On top of the metal bath, there will collect-a layer of slag consisting of silicious or other material. This layer of slag is formed either from material contained normally in the ore itself or it may be derived from fluxing materials mixed with the ore before it reaches the desulfurizing and sintering apparatus. If preferred, however, the fluxing materials can be separately introduced into the furnace by means of a hopper and chute, such as is indicated by 18. 19 is a slag-tap adapted for the occasional or continual removal of the slag.- The tap 19 may discharge into a suitable slag car, such' as indicated by 20. The tap is located at such an elevation that the slag will be maintained at a level somewhat above that of the inner end of the sinter cake 11. I have found that, on account of its porous nature, the sinter cake is lighter than the slag and will consequently tend to float thereon. By submerging the inner end of the sinter cake its tendency to breakby its own weight is counteracted. 21 and 22 represent two sets of electrical contact devices arranged respectively above These contact devices may be of any preferred form, but' for purposes of illustration I have shown them as comprising a series of slidable spring-pressed rollers frictionally engaging with the' surfaces of the cake. These contact devices are connected by means of a suitableconductor with one terminal of an electric generator. The other generator terminal is connected with a stationary electrode or contact plate 23 located in the bottom of the furnace. This contact plate is preferably formed of carbon and by means of it electrical connection is established to the bathof metal in the furnace.

The sinter cake 11, on account of the metal contained therein, forms an electric conductor-having a rather high resistance and the electric generator with which it is connected by means of the contacts 21 and 22 and the carbon plate 23 has suflicient voltage to permit the completion of an electric connection between the end of the sinter cake and the molten metal beneath it, the current pmsolid cake at substantially the some art of the furnace. As the sinter cake is me ted the ure metal is separated by gravity and unites ltmlf with the mass of metal in the furnace.

The slag and impurities float on top of the single unitary operation, as in certain cases metal and are withdrawn through the tap 19. The passage of the electric current through the sinter cake tends toheat it on account of the electricai resistance of the cake itself. It will be noted that the cake is subjected to four separate heating influences. First, the heat of sintering, which is retained as the cake passes into the furnace; second, the heat caused by the passage of the current through the sinter cake; third, the heat. derived by conduction and radiation from the hot metal and slag; and fourth, the heat from the electric action at the end of the cake. It will, therefore, be noted that,

on account of the. heating influences to whichthe cake is subjected before it reaches the smelting point, comparatively little additional heat need be cause melting.

I am aware that smelting by electrical,

mentary condition. By using my invention it is possible to agglomerate orsinter and smelt the ore by one contmuous operation,

' and onthis account my improved. process is carried out much more economically than those previously proposed. I do not desire, however, to limit my improved process to a it may be found possible or desirable to carry out t erationsi First, the sintercake maybe formed either in lon bars or in smaller fragof. the apparatus which I have described.

One of the advantages incident to myimproved process is that the sinter-electrode may be'so made up previous to its entrance,

into the furnace that its chemical com osition, including the necessary fluxes, wil be generated at this point to.

e process by two distinct separate opchemical reactions of the sintering processes are similar to those of the smelting processes,-

and therefore the sinter cake may be considered as partly smelted before it enters the furnace.

I have shown and described the sinter cake as enterin the furnace substantially horizontally. lowever, it may be found possible or desirable to feed the sinter cake vertically or at some oblique angle. It may also be possible in certain modifications of my process to feed the cake into the furnace on edge.

I do not limit myself to a single sinter-electrode and in a co-pending application entitled Apparatus for sintering and smelting ores, filed March 31, 1910, Serial No.-552,580, I have shown and described an apparatus for feeding two oppositely moving sinter-electrodes and forming an electrlc action between them.

I do not claim as part of m y present in-- vention the apparatus which I have shown and described. This apparatus is described and claimed in a copending application by me, entitled Apparatus for sintering and smelting ores, filed'March 31,1910, Serial Neither do I claim in this case the process-of obtaining metal from ore which is initially in a fine condition which consists in forming the ore in a relatively thin layer or stream, sintering'the ore while in such layer. and introducing the sinter thus formed intoa smelting furnace where it is smelted; as such process is made the subin my co-pending exactly right for the most economical and efiicient smelting and for the formation of .the correct chemical slag and other products.

The quantity sulfur in the case of sulfid ores or of carbon in the. case of iron ores may 1 be left such that the metalmatte or'regulus resulting ifrom the smelting will exactly I what is"desired. Another advanta is that gredients ofthe sinter cake is conducive of the extremely intimate mixturero the-'inject of my aforesaid application No.44OA-04, for process of sintering and smelting ores;

nor do I here claim the process oftreating porous metalliferous sinter by bringing it into intimate contact with molten slag that is maintained at a temperature sufficient to cause smelting of the sinter, as that process is made the subject-matter of and claimed application No. 636,296,

filed June 30, 1911. 1

What I claim is 1. The herein described process (if-sintering and smelting ore, which consists in sintering a layer of ore into a. continuous sinter cake, continually moving the said cake away from the region of sintering, subjecting the cake intermediateits ends to the action of an .electric current, and subjecting it at its advance end to the action of an electriccurrent which )asses from the end of the cake to arelatlvely; stationary conductor body, substantially as setfortln.

2. Th e herein described )roces's ofsintering and smelting ore,'wh1c cons sts n smtering a layer of'ore into a continuous sin-- ter cake, continually movin the cake away from the region of. format on and sub -ectmg thesaid icake to the. ac't'ionof an electric current, ,the said current passing through the cake and from the advance end l' the cake to a. relatively stationary electrmlc. substantially as set forth.

The herezn described process ci' suitoring and smelting ore. which consists in'sinwring a layer of ore into a-continuous cake. and subjecting the said cake while it still retains the heat of sintering to the action of an electric current, the said current pass ing through the cake. and from the advance end of the cake to a rel-.zti-rely stationary electrode, substantially as set forth.

The herein described process of sintering and smelting ore of the class adapted to e sister-ed by the combustion of materials contained therein, which consists in arranging the ore in a continually moriug layer, igniting the layer to cause combustion and sintering and subjecting the sintered layer to the action of an electric current, while it still retains the heat of si'ntering, the said current passing through the cake, and from the advance end of the cake to a relatively stationary electrode, substantially as set forth.

5. The herein described process of sinte1= ing and smelting ore; which consists in forming a continuous cake of sintered ore, continually moving the cake away from the region of formation, smelting the advance end of the said moving cake, and passing an electric current through the said cake intermediate its ends to raise the temperature thereof, substantially as set forth.

6. The herein described process of sintcring and smelting .ore, which consists in sintering a layer of ore into a continuous sinter cake, continually moving the cake away from the region of sintering, smelting the advance end of the said moving cal-:0 aa'l subjecting the cake intermediate its ads to a heating influence separate from the smelting means, substantially as set forth.

, 7. The-herein described process of smelting and sintering ore,-which consists in sintering a layer of ore into a continuous sinter cake, continually moving the cake away from the region of sintering, smelting the advance end of the moving cake and subjecting the cake intermediate its ends .toi-a plurality of independent heating influences each separate from the smelting means, substantially as set forth.

8. The herein described process of ore treatment, wh1ch consists in smtermg a layer of oreinto a continuous smtcr cake,

continually- .moving the said cake as it is formed away from the region of sinterin and passing an electric current through the said moving cake to raise the temperature ing relative movement between the cakeand the region of sintering, and passing an elec BEST AVAILABLE trio current through the said cake to raise the temperature thereof, substantially asset forth.

10. The herein described rocess of ore treatment, which consists in'smtering amass of ore causing relative movement between the ore mass and the region of sintering, and passing an electric current through the said mass while it retains the heat of sintering to further raise the temperature thereof, substantially as set forth- 11. The herein described ment for ore of the class a apted to be si'ntered by the combustion of materials contained therein, which consists in arranging the are in a continuously moving layer, igniting the layer to cause combustion and sintering, and subjecting the sintered layer to the action of an electric current, while the. heat of sintering is retained, to further raise the temperature thereof, substantially as set forth.

12. The herein described process of ore treatment which consists in arranging the ore in a continuously moving layer, subjecting the layer to a heating action and then passing an electric current through it, the said current passing through the layer and from the advance end of the layer to a stationary conductor body, substantially as set forth.

13. The herein described process of ore treatment which consists in continually forminga continuous homogeneous cake of material adapted to be smelted, causing the said cake to be heated, continually moving the said cake away from the region of 'formation and passing an electric current through the advance part of the said moving cake, substantially as set forth.

14. The herein described process of sintering and smelting ore, which consists in continually forming a.,continuous layer of the ore, subjecting the layer to the action of heat to cause sintering, continually moving the ore away from the region of forming.

and sintering, subjecting the forward end of the sinter cake to a continual smelting action, and applying heat to the said layer at points intermediate the. region of sintering and the region of smelting, the said heat being derived independently of the heat of sintering and of the heat of smelting, substantially as set forth.

15. The herein described process of sintering and smeltin ore masses containing combustible ingredients, which consists in continually forming a continuous layer'of the ore,- together with the said combustible ingradients, causing the combustion of the said the region of sintering, subjecting the forward end of the sinter cake to a continual rocess of treat- [combustible ingredients within the ore mass smelting action, and applying heat to the cake at points intermediate the regionof sintering and the region of smelting, the said heat being derived independently of the heat of sintering and of the heat of smelting, substantially as set forth. a

,16. The herein described process of ore treatment which consists in continually forming a continuous layer of the ore, continually moving the said layer away from the region of formation, sub ecting the layer to a heating action at points adjacent the region of formation, continually subjecting the forward end of the lay ato a smelting action, and applying heat to the ore at points intermediate the region of initial heating and the region of smelting, the said heat being derived independently of the heat of the said initial action and of the heat of smelting, substantially as set forth.

17 The herein described process of sintering and smelting ore, which consists in 0011- tinually forming a layer of the ore, continually moving the said layer away from the region of formation, subjecting the layer to heat at points adjacent the region'of formation to cause sintering, subjecting the forward end of the sintering layer to a smelting action, and passing an electric current through the layer at points intermediate the region of sintering and the region of smelting to raise the temperature thereof, substantially as set forth.

18. The herein described process of sintering and smelting ore masses containing combustible ingredients which consists in forming a continuous layer of the ore, together with the said combustible ingredients, causing the combustion of the said the region of smelting to raise the tempera- 'tu e thereof, substantially as set forth.

9. The herein described process of ore treatment, which consists in continually forming a continuous layer of the ore, continually moving the layer away from the region of formation, subjecting the layer toa heating action at points immediately adj acent the region of formation, subjecting the advance end of the said layer to a smelting action, and passing an electric current through the layer at points intermediate the region of the initial action and the region of smelting to raise the temperature of the layer, substantially as set forth.

20. The here' described process of sintering and smeltin ore, which consists in continually forming a continuous layer of the ore, continually sintering the said layer into a continuous cake, continually moving the cake away from the region of forming and sintering, continually subjecting the for .ward end of the cake to electric action to cause smelting, and applying heat to the said layer at points intermediate the region of sintering and the regicn of smelting electric action, the said heat being derived independently of the heat of sintcring and of the heat of the smelting action, substantially as set forth.

' 21. The herein describedproccss of s intering ore, which consists in continually forming a continuous layer of the ore, continu ally moving the layer away from the region of formation, applying heat to thelayer at points immediately adjacent the region of formation to cause sintcring, continually subjecting the forward end of the resulting sinter cake to electric action to cause smelt ing, and applying heat to the said la yer at points intermediate the region of sintering and the region of the electric smelting 21w tion, the said heat being derived independently of the heat of sintering and of the heat of smelting, substantially as set forth.

22. The herein described process of sintering and smelting ore masses containing combustible ingredients which consists in continually forming a continuous layer of the .ore together with the said combustible ingredients, causing combustion of'the said combustible ingredients to effect sintering, continually moving the resulting sinter cake away from the region of formation and sintering. subjecting the forward end of the sinter cake to electric action to cause smeltregion of formation, subjecting the layer at points immediately adjacent the ,region of formation to a heating action, continually subjecting the forward end of the layer to electric action to cause smelting, and applying heat to the layer at points intermediate the region of the initial heating action and the region of smelting action, the said heat being derived independently of the heat of the initial heating action and of the heat of smelting, substantially as set'forth.

24. The'herein described process of sintering and smelting ore masses containing combustible ingredients, which consists in continually forming a layer of the ore together with the combustible ingredients, causing combustion of the said combustible ingredients at points adjacent the region of formation to effect sintering of the layer, continually moving the resulting sinter cake away from the region of forming and sintering, passing an electric current through the moving cake at points beyond the region of sintering, and subjecting the forward end of the cake to electric action to cause smelting, substantially as set forth.

25. The herein described process of ore treatment which consists in continually forming.a.continuous layer of the ore, con-.

tinually moving the layer away from the region of formation, subjecting the layer to a heating action at points immediately adjacent the region of formation, passing an electric current through the layer at points beyond the region of the initial heating action, and subjecting the forward end of the layer to electric action to cause smelting, substantially as set forth.

26. The herein described process of sintering and smelting fine ore which consists in forming the ore into relatively thin and subintroducing this mass endwise into the free space of a smelting furnace above a fused bath formed by the smelting of the material being treated, causing a current of electricity to pass from the end of the said rigid mass of material into the bath and thereby smelting the former' and maintaining the latter in fused condition, and finall separating the metallic parts of the bat from the other components thereof.

28. The herein described process of recovering metal from metal-bearing material that is initially in a finelydivided condition, which consists in agglomerating the said material into a rigid mass that is highly and uniformly porous throughout, introducing this mass endwise into a smelting furnace above and across a fused bath formed by the smelting of the material being treated, causingthe end of the mass to come in contact with the said fluid bath whereby it is partially supported thereby,

causing a current of electricity to pass through the said rigid mass of material and from it into the bath, whereby the former is smelted and the latter maintained in fluid condition, and finally separating the metallic from the other component parts of the bath.

In testimony whereof I affix my signature, in presence of two witnesses.

ARTHUR s. DWIGHT. Witnesses H. J. STEI-ILI, C. M. STANLEY. 

